There are quite a number of occurrences in the kernel of the pattern
if (dst != src)
memcpy(dst, src, walk.total % AES_BLOCK_SIZE);
crypto_xor(dst, final, walk.total % AES_BLOCK_SIZE);
or
crypto_xor(keystream, src, nbytes);
memcpy(dst, keystream, nbytes);
where crypto_xor() is preceded or followed by a memcpy() invocation
that is only there because crypto_xor() uses its output parameter as
one of the inputs. To avoid having to add new instances of this pattern
in the arm64 code, which will be refactored to implement non-SIMD
fallbacks, add an alternative implementation called crypto_xor_cpy(),
taking separate input and output arguments. This removes the need for
the separate memcpy().
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When requesting a fallback algorithm, we should propagate the
NEED_FALLBACK bit when search for the underlying algorithm.
This will prevents drivers from allocating unnecessary fallbacks that
are never called. For instance, currently the vmx-crypto driver will use
the following chain of calls when calling the fallback implementation:
p8_aes_ctr -> ctr(p8_aes) -> aes-generic
However p8_aes will always delegate its calls to aes-generic. With this
patch, p8_aes_ctr will be able to use ctr(aes-generic) directly as its
fallback. The same applies to aes_s390.
Signed-off-by: Marcelo Henrique Cerri <marcelo.cerri@canonical.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Instead of unconditionally forcing 4 byte alignment for all generic
chaining modes that rely on crypto_xor() or crypto_inc() (which may
result in unnecessary copying of data when the underlying hardware
can perform unaligned accesses efficiently), make those functions
deal with unaligned input explicitly, but only if the Kconfig symbol
HAVE_EFFICIENT_UNALIGNED_ACCESS is set. This will allow us to drop
the alignmasks from the CBC, CMAC, CTR, CTS, PCBC and SEQIV drivers.
For crypto_inc(), this simply involves making the 4-byte stride
conditional on HAVE_EFFICIENT_UNALIGNED_ACCESS being set, given that
it typically operates on 16 byte buffers.
For crypto_xor(), an algorithm is implemented that simply runs through
the input using the largest strides possible if unaligned accesses are
allowed. If they are not, an optimal sequence of memory accesses is
emitted that takes the relative alignment of the input buffers into
account, e.g., if the relative misalignment of dst and src is 4 bytes,
the entire xor operation will be completed using 4 byte loads and stores
(modulo unaligned bits at the start and end). Note that all expressions
involving misalign are simply eliminated by the compiler when
HAVE_EFFICIENT_UNALIGNED_ACCESS is defined.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since commit 3a01d0ee2b ("crypto: skcipher - Remove top-level
givcipher interface"), crypto_spawn_skcipher2() and
crypto_spawn_skcipher() are equivalent. So switch callers of
crypto_spawn_skcipher2() to crypto_spawn_skcipher() and remove it.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since commit 3a01d0ee2b ("crypto: skcipher - Remove top-level
givcipher interface"), crypto_grab_skcipher2() and
crypto_grab_skcipher() are equivalent. So switch callers of
crypto_grab_skcipher2() to crypto_grab_skcipher() and remove it.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This adds the module loading prefix "crypto-" to the template lookup
as well.
For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly
includes the "crypto-" prefix at every level, correctly rejecting "vfat":
net-pf-38
algif-hash
crypto-vfat(blowfish)
crypto-vfat(blowfish)-all
crypto-vfat
Reported-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:
https://lkml.org/lkml/2013/3/4/70
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull crypto update from Herbert Xu:
"Here is the crypto update for 3.9:
- Added accelerated implementation of crc32 using pclmulqdq.
- Added test vector for fcrypt.
- Added support for OMAP4/AM33XX cipher and hash.
- Fixed loose crypto_user input checks.
- Misc fixes"
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (43 commits)
crypto: user - ensure user supplied strings are nul-terminated
crypto: user - fix empty string test in report API
crypto: user - fix info leaks in report API
crypto: caam - Added property fsl,sec-era in SEC4.0 device tree binding.
crypto: use ERR_CAST
crypto: atmel-aes - adjust duplicate test
crypto: crc32-pclmul - Kill warning on x86-32
crypto: x86/twofish - assembler clean-ups: use ENTRY/ENDPROC, localize jump labels
crypto: x86/sha1 - assembler clean-ups: use ENTRY/ENDPROC
crypto: x86/serpent - use ENTRY/ENDPROC for assember functions and localize jump targets
crypto: x86/salsa20 - assembler cleanup, use ENTRY/ENDPROC for assember functions and rename ECRYPT_* to salsa20_*
crypto: x86/ghash - assembler clean-up: use ENDPROC at end of assember functions
crypto: x86/crc32c - assembler clean-up: use ENTRY/ENDPROC
crypto: cast6-avx: use ENTRY()/ENDPROC() for assembler functions
crypto: cast5-avx: use ENTRY()/ENDPROC() for assembler functions and localize jump targets
crypto: camellia-x86_64/aes-ni: use ENTRY()/ENDPROC() for assembler functions and localize jump targets
crypto: blowfish-x86_64: use ENTRY()/ENDPROC() for assembler functions and localize jump targets
crypto: aesni-intel - add ENDPROC statements for assembler functions
crypto: x86/aes - assembler clean-ups: use ENTRY/ENDPROC, localize jump targets
crypto: testmgr - add test vector for fcrypt
...
Replace PTR_ERR followed by ERR_PTR by ERR_CAST, to be more concise.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression err,x;
@@
- err = PTR_ERR(x);
if (IS_ERR(x))
- return ERR_PTR(err);
+ return ERR_CAST(x);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Some hardware crypto drivers register asynchronous ctr(aes), which is left
unused in IPSEC because rfc3686 template only supports synchronous block
ciphers. Some other drivers register rfc3686(ctr(aes)) to workaround this
limitation but not all.
This patch changes rfc3686 to use asynchronous block ciphers, to allow async
ctr(aes) algorithms to be utilized automatically by IPSEC.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)). The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
type T;
T x;
identifier f;
@@
T f (...) { <+...
- ERR_PTR(PTR_ERR(x))
+ x
...+> }
@@
expression x;
@@
- ERR_PTR(PTR_ERR(x))
+ ERR_CAST(x)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Raw counter mode only works with chainiv, which is no longer
the default IV generator on SMP machines. This broke raw counter
mode as it can no longer instantiate as a givcipher.
This patch fixes it by always picking chainiv on raw counter
mode. This is based on the diagnosis and a patch by Huang
Ying.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This generator generates an IV based on a sequence number by xoring it
with a salt. This algorithm is mainly useful for CTR and similar modes.
This patch also sets it as the default IV generator for ctr.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As discussed previously, this patch moves the basic CTR functionality
into a chainable algorithm called ctr. The IPsec-specific variant of
it is now placed on top with the name rfc3686.
So ctr(aes) gives a chainable cipher with IV size 16 while the IPsec
variant will be called rfc3686(ctr(aes)). This patch also adjusts
gcm accordingly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When the data spans across a page boundary, CTR may incorrectly process
a partial block in the middle because the blkcipher walking code may
supply partial blocks in the middle as long as the total length of the
supplied data is more than a block. CTR is supposed to return any unused
partial block in that case to the walker.
This patch fixes this by doing exactly that, returning partial blocks to
the walker unless we received less than a block-worth of data to start
with.
This also allows us to optimise the bulk of the processing since we no
longer have to worry about partial blocks until the very end.
Thanks to Tan Swee Heng for fixes and actually testing this :)
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds countersize to CTR mode.
The template is now ctr(algo,noncesize,ivsize,countersize).
For example, ctr(aes,4,8,4) indicates the counterblock
will be composed of a salt/nonce that is 4 bytes, an iv
that is 8 bytes and the counter is 4 bytes.
When noncesize + ivsize < blocksize, CTR initializes the
last block - ivsize - noncesize portion of the block to
zero. Otherwise the counter block is composed of the IV
(and nonce if necessary).
If noncesize + ivsize == blocksize, then this indicates that
user is passing in entire counterblock. Thus countersize
indicates the amount of bytes in counterblock to use as
the counter for incrementing. CTR will increment counter
portion by 1, and begin encryption with that value.
Note that CTR assumes the counter portion of the block that
will be incremented is stored in big endian.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch implements CTR mode for IPsec.
It is based off of RFC 3686.
Please note:
1. CTR turns a block cipher into a stream cipher.
Encryption is done in blocks, however the last block
may be a partial block.
A "counter block" is encrypted, creating a keystream
that is xor'ed with the plaintext. The counter portion
of the counter block is incremented after each block
of plaintext is encrypted.
Decryption is performed in same manner.
2. The CTR counterblock is composed of,
nonce + IV + counter
The size of the counterblock is equivalent to the
blocksize of the cipher.
sizeof(nonce) + sizeof(IV) + sizeof(counter) = blocksize
The CTR template requires the name of the cipher
algorithm, the sizeof the nonce, and the sizeof the iv.
ctr(cipher,sizeof_nonce,sizeof_iv)
So for example,
ctr(aes,4,8)
specifies the counterblock will be composed of 4 bytes
from a nonce, 8 bytes from the iv, and 4 bytes for counter
since aes has a blocksize of 16 bytes.
3. The counter portion of the counter block is stored
in big endian for conformance to rfc 3686.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
